MagicLock vs SOURCEdefender — device-bound licensing vs encrypted loading

SOURCEdefender encrypts Python source files with AES and decrypts them transparently at import time — a clean, simple answer to "can someone read my .py files?". It deserves credit for making source encryption genuinely easy, and its time-limited scripts are a nice touch for demos. MagicLock and SOURCEdefender are the two most directly comparable tools on this list, because both encrypt rather than obfuscate — the difference is what happens after encryption.

What SOURCEdefender does well

• Straightforward AES encryption of .pye files with transparent import — minimal setup, minimal concepts.
• Time-limited scripts for expiring demos.
• A simple subscription and a small API surface — easy to adopt in an afternoon.

The different question each tool answers

Encrypting a file protects its confidentiality. But shipped software has a second question: which machines are allowed to turn that ciphertext back into a running program? A file that decrypts anywhere the loader runs protects reading, not running.

MagicLock binds each artifact to authorized devices: activation registers a machine's fingerprint, and decryption succeeds only there — verified fully offline at every run through a five-step gate (authenticity, validity, device, entitlement, freshness). Copy the artifact anywhere else and it stays ciphertext.

Side by side

Based on public documentation as of the date below — verify current capabilities at sourcedefender.co.uk.

When SOURCEdefender may fit better

• You need only confidentiality — keeping source unreadable in transit and at rest — and licensing is out of scope or handled elsewhere.
• You value the smallest possible concept count over device control.

When MagicLock fits better

• You need to control where code runs, not only whether it can be read — per-seat licensing enforced by encryption.
• You ship models or data assets that need the same per-device protection as the code.
• You want to be able to act after shipping — stop, restart, or permanently deny a specific artifact from a portal.
• You want a compiled tier for the hardest targets.

Both tools encrypt; MagicLock's premise is that for commercial software, who can run it is the question that matters. Try it free for 48 hours — start here.